<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="box">1231321</div>
<div id="box1">1231321</div>
<div id="box2">1231321</div>
<div id="box4">1231321</div>
</body>
</html>
<script src="js/jquery-1.10.1.js"></script>
<script>
    $(function () {
        //        通过get()方法可以将jquery对象转化为原生的DOM对象
        $("#box").css("color","blue");
        $("div").get(2).style.background ="yellow"
    })
</script>